Oil-exporting nations in the Middle East and North Africa are expected to earn about $530 billion from sales of crude oil this year, compared with $300 billion in 2003, according to the International Monetary Fund.

Middle Eastern countries account for less than 1 percent of $1.5 trillion of foreign direct investment in United States businesses and real estate, according to a recent report by the Congressional Research Service. That lags far behind the largest foreign investors: Britain, Japan, Germany, the Netherlands and France.